There are multiple bands with the name Witness:

1) Witness (known as "Witness UK" in the U.S.) were an alternative rock band formed in Wigan, UK in 1997. The lineup consisted of Gerard Starkie (Vocals, Guitar), Ray Chan (Guitars), Dylan Keeton (Bass Guitar), John Langley (Drums); and on their 2nd album, Julian Pransky-Poole (Guitars). The band released two albums, 1999's Before The Calm (which received a 9/10 in the NME) and 2001's Under A Sun, before splitting in 2004. Starkie went on pursue a solo career. http://www.witness.uk.com

2) Witness was an 80s hard rock band that only released a self-titled album in 1988. Fronted by Debbie Davis, the band has gained a cult following among hard rock and melodic rock fans. The album is highly sought-after and fetches high prices in online auctions. The sound of Witness has been compared mostly to Vixen. Fan-favorite catchy songs include "You're Not My Lover", "When It Comes From The Heart" and "Desperate Lover".

3) Witness is a Christian hip-hop and reggae artist from Birmingham, West Midlands. He is known for his uplifting and anti-violence lyrics, as shown in his track "Tooled Up For School". It is also known that Witness has performed in various Midlands schools including Wodensborough CTC in Wednesbury in order to spread his message and promote his work.