This is my outline

Thesis: Graffiti can be vandalism but it can also be art that can help a community.

1. Because it is a way to express oneself     

“There are four primary motivating factors for graffiti vandalism: fame, rebellion, self-expression and power.” – Houston, Taxes Gov.
“Art is about expression, creativity, freedom, asking and raising questions, protesting, analysing for the creative type to get things out of their system. For the underdog to take a stand. For artists to step beyond convention. and street, urban art and graffiti is the best proof of this.” – graffitikings
2.  Because it can turn a boring old brick wall into a piece of art as a result; graffiti can decorate a community in some peoples eyes. 

“Graffiti isnt just limited to painting on walls. Its about interaction within the public space. And so many different types and styles of street and urban art come under that umbrella.” –
3.  Because it can bring hope and joy to people. Like murals of people who have passed, brush type which is creating a painterly result and usually is of people.

“Graffiti has been around for as long as humans have had paint and walls to daub it on, but in recent decades graffiti has evolved away from scribbles and crude drawings to sometimes breathtaking works of art.” –
“Graffiti in the street makes people happy; it makes their day and their commute more interesting. It adds character to what would otherwise just be grey and boring. It reminds people to feel alive. It wakes people up. It inspires. Motivates. And sometimes it can make people think. Street art takes the ‘normal’ and makes it a thousand times more interesting.” – ABQ News