Forensics are said to be the ultimate in securing convictions, but how reliable are they?

I did some research on the case of Shirley Banks and found an interview with the forensic tester who ran some tests on buttons apparently found at the scene where her body was found. She was naked.
Plastic doesn't tarnish easy, however the thread was said to be present on a button.

Are you listening?

Do we know she bought a dress?

No. We don't. Her card purchase certainly wouldn't have contained so much detail and any evidence of what she purchased would have been on the receipt which disappeared with her.

Still listening?

The police found a small plastic carrier bag in John Cannan's possession for smaller clothing items. Police claim the shop had run out of large bags.

Still listening?

I don't believe they would have crammed a dress into a small bag.

Could this be proof she possibly bought something smaller or Cannan had that bag as a result of another crime?

One month after Suzy Lamplugh dissapeared, a female corpse was found in Ashdowne Forest ( Dorset PCC old territory) August 31st ( 1986) and, get this...Crimewatch reconstruction said the body was found wrapped in curtains AND some nightdresses were relevant to the murder scene.

John Cannan during police interview started discussing curtains.

He also claimed he had a lawnmower in his boot.( Why would he need one living in a communal block of flats?).

Shani Warren had grass cuttings in her boot when she was murdered.


Thoughts?

I find it shocking how some crimes are not solved. I am.suspecting they are purposely left that way.


This research (and other issues I will put here as I go) brought everything home to me of how the system really doesn't care. They carry on trying to convince people that reports of abuse will be taken seriously.

Some things can't be unseen or unknown.
All of the effort that went into investigating historical crime, but they have stayed away from revisiting all of this on missing/ murdered women.

It's an insult to all women who suffer and to any men who have been held to account for much less.
It puts the CPS and police in a very bad light.

Still, they will keep putting unsuitable , misogynistic and abuser types into power.

Like I said... They really DO NOT care and doesn't it show?