WANNABE Miss Marple bosses are sifting through CCTV footage in their bid to victimise union activists, rail workers said yesterday.

At rail union RMT’s annual general meeting in Exeter, delegates said managers were going to “appalling lengths” to build flimsy disciplinary cases with the video footage.

Delegates unanimously backed a resolution calling for “clear and strict guidelines” on how CCTV footage can be used.

Central Line West delegate Ross Marshall said: “We’ve heard several cases where managers were taking weeks and weeks to trawl through CCTV.”

East Midland Central delegate Matthew Partridge said: “My branch has lost six members in the last year due to a company using CCTV against them.

“They were bloody good activists, and it was only due to us going to a ballot that we managed to get them an agreement.”

The motion said managers were “trawling” through CCTV to “enhance” disciplinary cases, even when supposed offences dredged up were completely irrelevant to the original accusation.

Dorset Rail’s Jim Buchanan said: “I’m sick and tired of amateur Miss Marple-ing.”

The conference also heard of a worrying reluctance from bosses to stand up for staff assaulted at work.

Staff at London Bridge Tube station recently balloted for industrial action after workers were disciplined over an incident with a violent passenger — but fell foul of new anti-strike laws.

“If you were listening to what the company were saying it was like our two members of staff were going round with baseball bats, The Sweeney style, battering people,” Mr Marshall said.

“I’m telling you that did not happen.”