Farrell's comments today echoed those of Lions head coach Warren Gatland, who said "there was no allegation of spying" aimed at the Australian camp and that he had "no issue" with the Australians videoing last week's Western Force game in Perth.
The Australian Rugby Union subsequently issued a statement, "flatly denying that anyone connected to the Wallabies has been involved in filming or watching the Lions at training".
Wallabies head coach Robbie Deans claimed the whole affair was "just a sideshow," and Lions assistant coach Farrell said: "We are not paranoid.
"If we are paranoid about getting things right then yes, we are. You've got to get things right.
"We are leaving nothing to chance. It is important we have everything covered on and off the field.
"We are trying to do our best on the field, and off the field we have to make sure that nothing gets in the way of the on-field stuff as well."
Security is evident at the Lions' training venues in Australia, although some of the work-outs have seen members of the public permitted to be in attendance, such as for a session at a Brisbane grammar school last week.
The Lions are now preparing for tomorrow's game against a Combined Country XV in Newcastle, and Jamie Heaslip has hailed the "great" presence of his fellow Irishman and four-time Lions tourist Brian O'Driscoll.
Heaslip, who succeeded O'Driscoll as Ireland captain, will run out behind his Leinster colleague tomorrow when O'Driscoll skippers the Lions for a second time on their Australia tour.
And it could be that the Country select will face the Lions' first Test threequarter line of Alex Cuthbert, O'Driscoll, Jamie Roberts and George North at Newcastle's Hunter Stadium, home of Newcastle Knights rugby league club.
"I have been lucky enough to have Brian captain me with Leinster, with Ireland, on the last (Lions) tour for one or two of the games and again last week (against Western Force)," number eight Heaslip said.
"I've been around him for a while now, and it's great to be either side of him - either captain of him or captained by him.
"Just being on the field beside the guy is great. He's a leader, both on and off the field, and he does a lot of stuff that you wouldn't necessarily see.
"He sets a really, really good example for players off the field and he backs that up with his performance and the way he goes about his business on the field. It's great to have him as captain."
Heaslip announced his Test team credentials through a strong display against the Force, and another powerful showing tomorrow would unquestionably turn up the heat on his Test team number eight selection rival Toby Faletau.
"The thing I try to bring from the last Lions tour in 2009 is the experience that I had, in different ways," he added.
"It's a really interesting and simple shape that we are playing. The back row has a pretty prominent role to play in it, and it's great to get your hands on the ball.
"Sometimes you get games where it opens up and you get to spread your legs, and sometimes you don't and you've just got to grind it out, just like against the Reds at the weekend.
"You just take what comes your way and take your opportunities but, most importantly, you just make sure you prepare for what's coming and you put in a lot of work."
Fly-halves Jonathan Sexton and Owen Farrell both missed training in Newcastle today, but Andy Farrell moved to allay any fears surrounding their fitness.
"Like every game of rugby, guys have got little knocks and tweaks, but there is nothing serious," Farrell said.
"Owen has just got a bit of a dead leg, that's all, so that is precautionary. Jonny was just a little bit tight (hamstring), but he's fine as well.
"They've got to recover properly, especially with the flights, so they had training off today, but they are fine.
"Rob (Kearney) trained this morning and he ran very well. He will be back with the boys, the non 23, tomorrow morning, and he will be looking to be fit for the weekend."
Assessing the Combined Country team's challenge, Farrell said: "For the 23 that are going to come against us, it's probably going to be the biggest game of their lives.
"You can play against anyone and for the first 20-25 minutes it's always going to be a battle. They will bring a lot of intensity and guts to the game."
Lions captain Sam Warburton, playing colleague Manu Tuilagi, Lions manager Andy Irvine, chairman Gerald Davies and chief executive John Feehan will tomorrow pay tribute to the first Lions captain Robert Seddon at a wreath-laying ceremony near Newcastle.
Seddon drowned in the Hunter River during the Lions' 1888 tour of Australia, and the Lions group will be joined by Australian Rugby Union president David Crombie and Newcastle MP Tim Owen in a tribute at Campbells Hill Cemetery.
Teams for the Combined Country XV versus the British and Irish Lions at the Hunter Stadium in Newcastle, Tuesday (kick-off 1030 BST).
Combined Country XV: N Trist; A Gibbon, L Catt, T Siaksini, T Cox; A Roberts, M Snowdon; H Hirsimaki, J Mann-Rae, T Metcher, P Battye, B Enever, R Stanford, J Butler, T Davidson (capt).
Replacements: T Kearney, D Evans, R Abraham, R Arnold, T Dyer, A McCormack, S McCarthy, D Ahwang.
Lions: S Maitland (Scotland); A Cuthbert (Wales), B O'Driscoll (Ireland, capt), J Roberts (Wales), G North (Wales); S Hogg (Scotland), C Murray (Ireland); A Corbisiero (England), R Hibbard (Wales), D Cole (England), R Gray (Scotland), I Evans (Wales), S O'Brien (Ireland), J Tipuric (Wales), J Heaslip (Ireland).
Replacements: R Best (Ireland), R Grant (Scotland), M Stevens (England), A-W Jones (Wales), T Faletau (Wales), M Phillips (Wales), J Davies (Wales), L Halfpenny (Wales).
Referee: Steve Walsh (Australia).
Assistant referees: Angus Gardner and James Leckie (both Australia).